Final answer:
The theme reflected in the final stanza of 'The Colored Soldiers' is that Black Americans’ willingness to fight in the Civil War helped unite the country.
Step-by-step explanation:
The theme reflected in the final stanza of the poem 'The Colored Soldiers' is Black Americans’ willingness to fight in the Civil War helped unite the country. The stanza emphasizes that the black soldiers who fought for Uncle Sam, despite the injustices they faced, have a rightful place in history and should be honored. Their courage and sacrifice in the war played a significant role in uniting the nation and cleansing the shame of slavery.